Lubricating apparatus



ug. 2H? H934 F, s BARKS v g LUBRICATING APPARATUS Filed May '7, 1931 3Sheets-Sheet 2 m, l FG.

Aug. 2E, E93@ F. s. BARKS LUBRICATING APPARATUS Filed May 7, 1951 3Sheets-Sheet 3 Patented` Aug. 2l,` 1934 UNITED STATES LUBRICATIN GAPPARATUS Frank S. Barks, St. Louis, Mo., assigner to LincolnEngineering Company, St. Louis, Mo., a

corporation of Missouri Application May 1, 1931, Serial No. 535,712

10 Claims.

This invention relates to lubricating apparatus, and with regard tocertain more specific features, to apparatus of this class for moreeectively handling high pressures.

Among the several objects of the invention may be noted the provision ofimprovements upon the structure described in my United States Patent No.1,805,303, dated May 12, 1931, for Lubricating apparatus; the provisionof apparatus of the class described which shall eliminate excessivepressures in grease return lines and parts associated therewith; theprovision of apparatus of the class described including improved plungerapparatus and heating means; and the provision of apparatus of thisclass which shall be simple in construction and effective in operation.Other objects will be in part obvious and in part pointe outhereinafter.

The invention accordingly comprises the elements and combinations ofelements, features of, construction, and arrangements o parts which willbe exemplified in the structure hereinafter described, and the scope ofthe application of which will be indicated in the following claims.

2g In the accompanying drawings, in which are illustrated several ofvarious possible embodif ments of the invention,

Fig. l is primarily a longitudinal section showing certain organizedelements of the invention 3@ (parts being diagrammatic);

Fig. 2 is a cross section taken on line 2-2 of Fig. i; Y

Fig. 3 is an enlarged detail of the lower righthand portion of Fig. i;

Fig. e is a view similar to Fig. 3 showing a modified form;

Fig. 5 is a view similar to Fig. 4 showing another modiiied form;

Fig. 6 is a vertical section taken through a barrel pump, which may beused in connection with the present invention;

Fig. '7 is an enlarged fragmentary section oi a plunger portion of theconstruction shown in Fig. 6;

Fig. 3 is a view similar to Fig. 7, but showing an alternative positionof parts, said parts being shown in elevation, rather than in section asin Fis. 7;

' Fig. 9 isv a horizontal section taken on line 9 9 of Fig. 6 on anenlarged scale; and,

Fig. l0 is a circuit diagram illustrating the use of the invention.

Similar reference characters indicate corresponding parts through theseveral views of the drawings.

(Cl. 18d- 7) Referring now more particularly to Fig. 1, there isillustrated at numeral 1 a driving motor or motivating means adapted todrive a 'cam 3 through gear reduction means 5. The cam 3, incoordination with a return spring '1 reciprocates a 60 plunger9 of amain pump 107 (see also Fig. 10) within a housing i1, the latter havingan outlet bushing 13 in which is located an outlet check valve 15leading to a pressure line 17.

At the end of the plunger 9 (Fig. 3) is aiilxed 65 a head 19 whichloosely ilts into a sleeve piston 21, the latter slidably fitting kthebore of said bushing 13. The central opening 23 of the piston 21 is ofshape similar to that of the head 19 but does not closely engagetherewith. Across the head 19 is positioned a pin 25 iitting into agroove 2'7 oi the piston 2i. The effective space between the pin 25 andthe forward hardened face 29 of the plunger 9 is such that a lost-motionengagement is eected between the plunger and piston. Furthermore, thereis ample clearance between the plunger 9 and bore of bushing 13 totransmit iluid when they are separated.

When the plunger 9 is withdrawn to the left,` the piston 2i tends tolag, as shown in Fig. 3. so The check valve l5 being shut, the inducedsuction in the bore of bushing 13 immediately draws fluid between thehead 19 and piston 21, thus to fill said bore to the right of theplunger and piston. When next the plunger 9 moves to the right, 85 theface 29 contacts with the piston 21 to drive the latter forward and thusto expel iluid from the bushing 13 and to drive the same past the checkvalve 15.

The advantage of the above construction is that neither the piston 21nor plunger 9 needs to cross any port over which there is a machinedfit. Thus a perfect seal and higher pressures may be more eiectivelymaintained. The volumetric eiliciency of the device is high, because noexcessive vacuums are drawn before crossing a valve port. The iluid isdrawn in from the very beginning of the suction stroke, rather thanbeing delayed in its entry for a period of time and then quicklydelivered over a small duration of time, as in prior ported devices ofthis class.

Fig. d shows an alternative form of plunger organization in which theplunger 9 is provided with a sealing face 31 for contacting with anannular piston 33. The head 35 of the plunger is 105 annular-ly spacedfrom the piston 33 and is hollow as shown at numeral 37. A collar 39 ispro vided to withdraw the piston 33, the distance between collar 39 andface 31, as compared with the length oi piston 33, providing thedesirable 110,

lost-motion engagement. Communicating passages 41 connect the opening 37with the rear of the piston 33 when the plunger 9 is withdrawn. Thusfluid is driven to a' position ahead of the piston 33. When the plungerreturns, the seat 31 engages the piston 33 to push the same, thusclosing oif the communications 41 and driving the charge past the checkvalve 15.

In Fig. 5 is shown another embodiment of the punger, wherein likenumerals designate like parts. This form is like the form of Fig. 4,except that the head 43 is not hollow and a pin 46 is substituted forthe collar 39 in order to effect lost-motion engagement. Thus this formpartakes of the Fig. 1 form in the pin construction and externaldelivery, but also of the Fig. 4 form as to the cylindrical spacingbetween head and piston, rather than conical as in Fig. l.

Referring again to Fig. 1, the housing 11 is built upwardly to effect anupward directed passage 45 in the lower end of which is positioned arelatively fine strainer 47 and in the upper end of which is positioneda relatively coarse screen 49. The purpose of the upper screen 49 is tostop relatively large particles or concretions of grease from passing tothe lower, finer screen 47, the latter screening out finer undesirableparticles.

Between the screen 47 and 49 is crosswise located a chamber 51, thepurpose of which is to carry an electrical heating element 53. Theelement 53 softens the grease or the like and thus enhances the flowfrom above, particularly when the grease would be otherwise cold. Theheater 53 is energized from a suitable circuit 2.

Above the casting 11 is iitted a capV 55 having coaxial cylinders 57 and59 carrying pistons 61 and 63 respectively. The pistons 61 and 63 arejoined by a piston rod 65. It will be seen that the pistons 61, 63 andtheir piston rods 65 iloat freely in the cylinders 57 and 59. The uppercylinder 59 is capped as shown atnumeralv 67. An air connection 69 ismade above the piston 83 and a grease connection 71 is made below thepiston 61. A gauge 73 is applied as an auxiliary to ascertain pressuresbelow the piston 61.

Referring to Figs. 6 to 8, a description will be given of a pump 111which is to be used in connection with the pumping apparatus of Fig. 1.This description is given at this point in order that the operation ofthe invention as a whole may be understood more clearly.

In Fig. 6 is shown a barrel 75 of a class in which lubricants and thelike are ordinarily delivered. This barrel carries a bushing 77 adaptedto have threaded therein a closing cap. When the barrel is received,said cap is removed. and a bushing 79 screwed therein. This bushing 79has for its purpose the receiving of an outlet connection 81 associatedwith a pump barrel or tube 83. the latter being adapted to enter thelower reaches of the barrel 75. Associated with the outlet member 81 isa grease outlet 85 which, as shown in Fig. 10, is in connection with thegrease inlet 71 by means of a line 87.

Above the member 81 is a supporting structure 89 for an air pumpcylinder 91 having therein a reciprocating piston 93 which has a pistonrod 95 extending down into said cylinder 83, lthe rod The purpose of thecross Full-stroke valve gear of this general class has already beendescribed in connection with my United States Patent 1,858,979, datedMay 17, 1932, for Pump. It will here suillce to state that the inlet forair is brought into one side of the valve gear, Aas shown in numeral 105in Fig. .0. When the-valvev stem 106 is in a position such as shown inFig. 6, air may flow through passage 4 .to the lower side of the piston93, thus tending to lift the piston. Exhaust occurs from the upper sideof the piston 93 through the outlet 6 and out around the end 108 of thestem 106. In its alternate position, the stem 106 covers the outlet port6, air being then charged above the piston 93 and exhaust occurring frombelow the piston 93 through a port 113 opposite which at this time islocated a recess 115 in the valve stem 106.

The lower end of the piston rod 95 carries a hollow piston 117, shownmore particularly in Figs. 7 and 8. This piston 117 comprises a hollowhead 119 having inlet ports 121 and outlet ports 123. The inlet ports121 are slidably covered and uncovered by a sleeve 125 which, at itslower end, seats upon the closure 127. 'I'he sleeve 125 is normallypressed into closed position on the closure 127 by means of acompression spring 129 reacting against a collar 131. The sleeve 125 ofthe piston 11.7 is slidably sealed to the cylinder 83 by means of apiston ring 139.

A foot valve 133 at the lower end of the cylinder 83 permits entry ofgrease but prevents reverse exit therethrough. A castellated open bottom135 to the cylinder 83 permits entry of grease into the cylinder 33 frombelow, even though the cylinder 83 be resting on the bottom of thebarrel 75. A strainer 137 ensures that foreign material will not clogthe valve 133. A small opening 134 is provided in the valve 133. Thisopening has a resistance to air flow which is relatively low andresistance to grease flow which is relatively high. A diameter of theorder of 1% of an inch and over has been found effective for the purposeto be set out. The exact size depends upon the weight of grease beingpumped. the diameter given being for medium grease.

The operation of the elements shown in Figs. 6 to 8 is as follows:

When the piston 117 is driven down. the foot valve 133 closes. 'I'hecharge trapped above the foot valve 133 forces the sleeve 125 againstthe spring 129 thus exposing the inlet ports 121. Hence, grease isforced through the inlet ports 121 and out of the outlet ports 123 to aposition above the piston 117. Upon retraction of the piston 117, thesleeve 125 re-seats on the closure 127. This results in the charge abovethe piston 117 being driven out of the outlet 85; whereas below thepiston 117, the foot valve 133 is opened permitting drawing in of a-charge below said piston 117. The opening 134 substantially resistsreturn of grease but does lnot resist return of air. Hence thespring.129 will effect opening to grease passage but not to air passage,as when the supply in the barrel is exhausted. 'Ihe result is that thisconstruction does not pump air after the grease is exhausted. Itistherefore of advantage in other applications where meters are use inthe outlet such as 85.

An air compressor 141 delivers air to the inlet 105 of the engine on thebarrel pump. It also delivers air pressure to the inlet 69 of thepressure boosting pump shown in Fig. 1.

It is clear that whenever the pressure in the lines 85 is above apredetermined amount, de-

termned by the ratio of the diameters of pistons 117 and 93, that thebarrel pump will cease to operate under the air pressure available fromthe compressor 141. In other words, the barrel pump (Fig. 6) will notstart to operate until the pressure in line 87 has dropped to apredetermined amount. On the other hand, said pres sure will not dropuntil grease is withdrawn from the casting 11 by means of the main pump107 shown in Fig. 1. Thus the barrel pump of Fig. 6 is a class exampleof automatically starting pump for supplying fluid to the main pump 107shown in Fig. l.

The pump 107 (which is a booster) pumps to the line 17 and said line 1'!passes to measuring valve apparatus such as described in said Patent1,805,303, which includes a line analogous to line 17 and another lineanalogous to the return line 109 shown herein. This return line (109herein), as shown in said patent,`sends certain grease returns to thesuction side of the pump 107 (see connection 8). The returns are underpressure which, if not relieved, vwill rise to a degree liable to burstthe castings of the pump 107. The present invention prevents saidbursting action and other deleterious results, by causing the pressureof said returns to be exerted against the piston 61, thus compressingthe air above the piston 63. The ratio or" the areas of the pistons 6land 63 is such that the air pressure available at the air pump 1h11 willby pressure force grease through the strainers 4.7 and 49 to the suctionside of the pump 107. The grease pressure is not of the order of thepressures that would be built up by the returning grease were itconfined.

The operation is as follows:

The barrel pump lll is supplied air by the air pump 141 or itsequivalent. The air pump 141 alsosupplies air above the piston 63.Whenever the pump 107 pumps grease to the line 17, the pressure drops inthe line 87. The drop is below the predeterminedvalue adapted to permitstarting of the grease pump lll which supplies grease to the pump 107through the lines 85, 87, 71 (Fig. 10). v

When return of grease under pressure occurs over the line 109 to thesuction side of the pump 107, either when the pump 107 is operating orwhen it is idle, the tendency is for the pressure within the casting 11to rise. When this occurs, the pressure is exerted on the piston 61which is reacted against by the pressure on piston 63. Thus the greasepressure of the returns, instead of rising deleteriously, rises onlyenough to cause compression in the cylinder 59 which, by the relativeareas of the pistons 61 and 63 is calculated to prevent rise in returnpressure such as might otherwise cause breakage. The pressure thusaccumulated in the casting 11 is again used when the pump 107 isrequired to deliver more grease through .the line 17, because thecompressed air in the cylinder' 59 re-expands to deliver grease frombelow the piston 6l to the plunger 9.

The device may be seen to comprise in effect an accumulator for thepressure of the grease returns. The energy of the non-expansive greaseis stored in the expansive air above the piston 63. Wheneverre-expansion of air above the piston 63 goes below that which the airpump 141 is adapted to supply, said pump 141 automatically starts andsupplies the deficiency. It is to be understood that the pump 141 mayhave substituted therefor stored air supply in communication with thecylinder 59, this being done by way ofva check valve or by directcommunication. It is to be 'understood that the grease may be suppliedto the pump 107 by other means than the barrel pump The motor 1 (Fig. 1)may be manually started and stopped, or clocked means may be used forstarting and stopping the same, or it may be responsive to the pressurein line 17 through a pressure-operated switch. These alternatives formno part of the present invention and will not be detailed here/in.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As' many changes could be made in carrying out the above constructionswithout departing from the scope ofthe invention, it is intended thatall matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimitmg sense.

I claim:

1. In apparatus of the class described, a lubri-v cant supply, a pumpfor receiving lubricant from said supply and ccmpressiong the same anddelivering the lubricant to measuring means which requires for operationrelief of lubricant under pressure to a line leading therefrom, a returnline adapted to convey relieved lubricant from said line to the supply,means for maintaining pressure on said supply, and an expansible chamberfor housing said supply, the pressure on the supply being less than thepressure caused by the pump in the return line.

2. In apparatus of the class described, a lubricant supply, a pump forreceiving lubricant from said supply compressing the same and deliveringthe lubricant to measuring means which requires for operation relief oflubricant under pressure to a line leading therefrom, a return lineadapted to convey relieved lubricant from said line tol the supply,means for maintaining pressure on said supply, a housing for saidsupply, movable means associated with said housing for varying thevolume therein, said movable means being subjected to lubricant pressureinside the same andexternal pressure outside of the same said externalpressure being such as to cause less pressure on the supply than thepressure caused by the pump in the return line. y

3. In apparatus of the class described, a chamoer for lubricant supply,a pump for delivering lubricant from said supply and delivering thelubricant to measuring means which requires for operation relief oflubricant under pressure to a line leading therefrom, a return lineadapted to convey relieved lubricant from saidline to the supply, meansfor automatically delivering lubricant under pressure to said chamber assaid pump delivers lubricant from Athe chamber, expansive meansassociated with said chamber for preventing excessive rise in pressure`upon entry of said returned lubricant, andy means for placing pressureon the expansive means, said last-named pressure being such as to causeless pressure on the supply than the pressure caused' by the pump insaid return line.

supply, means for supplying lubricant to said! container, an expansibleportion associated with said container, and kmeans for placing pressureon the expansive` means, said last-named pres sure being such as tocause yliess pressure on the supplythan the pressure caused by the pumpin said return line, said expansible portion re-k lubricant from saidsupply and delivering 'the lubricant to measuringimeans which requires-for operation relief of lubricant under pressure to a. line leadingtherefrom, a return line adapted kwto convey relieved llubricant from`said `line toy the supply, ymeans yfor automatically deliveringlubricant to said chamber under pressure as said `pump supplieslubricant from `ciatedwith said chamber for. preventing excessive`r 'thechamber y to the measuring means, said measuring means building uppressure in the return lineand causing return of lubricant through thereturn line, expansive means assorise in pressure upon `entry of` saidreturned lubricant,- and means for maintaining pressure on saidexpansive means externally of thecham-y ber, said last-named pressureeiecting pressure f inside said chamber which isless than the preswlrsure` built up in said return line by the measuring.

means. n

6.y In apparatus of the class described, a chamber for a lubricantsupply. a pump fory delivering lubricant from said supply `anddelivering the lubricant to measuring means which requires for;

operation relief `of lubricantr under pressure.r to

a line leading therefrom, a `return line adapted torconvey,relievedlubricant from said line to the supply, means for`automatically delivering lubricant to said chamber under pressure assaid pump supplies lubricant from the chamber to the measuring means,said measuring means building up pressure in the return line and causing-return of lubricant through the return line, expansive means associatedwith said chamber for preventing excessive rise in pressure upon entryof said returned lubricant, means for maintaining external pressure onsaid expansive means, said last-named means comprising compressed iluidhaving a pressure which exerts less pressure on the supply than themeasuring means on the lubricant in `said return line, said expansivevmeans comprising a plurality of connected pistons having area ratiosinversely as the pressures on opposite faces thereof.

7. In apparatus of the class described, a chamber for lubricant supply,a pump for delivering lubricant from said supply and delivering thelubricant to measuring means which requires for operation reliefoflubricant under pressure to a line leading therefrom, a return lineadapted to convey relieved lubricant from said line to the supply, meansfor automatically delivering lubricant to said chamber under pressure assaid pump supplies lubricant from the chamber to the measuring means,said measuring means building up pressure in the return line and causingreturn of lubricant through the return line. expansive means associatedwith said chamber for preventing excessive rise in pressure upon entryof said return, means for maintaining external pressure on saidexpansive means. said last-named means comprising compressed fluidhaving a pressure which exerts less pressure on the supply than themeasuring means on the lubricant in -saidreturn line, said expansivemeans comprising la plurality of connectedrpistons having area ratiosyinversely as the pressure toy be balanced thereby, the .smaller areabeing presented interiorly of the chamber.

8. In apparatus of the class described, a container for a.lubricantsupply, -a pump for delivering compressed lubricant fromsaidcontainer rand delivering the lubricant to measuring means whichrequires for operation thereof relief of lubricant underpressure toaline leading therefrom, a return line adapted toy convey relievedlubricant from said line to the supply, means for automaticallymaintaining pressure in said container on lubricantdelivered to saidpump as said pump supplies lubricant from the chamber to the measuringmeans, said measuring' means` Vbuilding-'up pressure in thereturn lineand ycaus- -ing return of lubricant through the return line;

and expansible means for maintaining the pres.- n

:sure in said ycontainer within a predetermined range below that whichis transmitted tothe relieved lubricant by the measuring means.

9. 'In apparatus of theclass described, a container for alubricantsupply, a pump forideliver ing compressed lubricant from Lsaid containeri and' delivering the lubricant to measuring means which requires foroperation thereof relief `of lubricant under pressure to a line leadingtherefrom, a return line adapted to" convey `relieved lubricant from`said line to the supply, means for automatically maintaining pressurein `said range below that which is transmitted to the re-r lievedlubricantby the measuring means and to store energy for use indelivering lubricant to said pump.

10. In apparatus of the class described a container fo'r lubricant, apump adapted to deliver lubricant therefrom under pressure anddelivering the lubricant to measuring means which requires for operationrelief of lubricant under pressure to a line leading therefrom, a returnline adapted to convey relieved lubricant from said line to the supply,means for supplying lubricant to said container as said pumpsupplieslubricant from the container to the measuring means, said measuringmeans building up pressure in the returnv line and causing return oflubricant through the return line, -an expansible portion associatedwith said container, and means for placing pressure on the expansivemeans, said last-named pressure being such as to cause less pressure onrthe supply than the pressure caused by the Imeasuring means in saidreturn line, said expansible portion responding by substantial increasein volume to increase of pressure in said container, said expansiblemeans comprising rigidly joined members of different areas, means forimpressing on the respective areas pressures in a predetermined ratio,whereby said members are held in one extreme position, said membersmoving to another position upon increase in pressure in said containerand being adapted`to return to the original position when said deliverypump withdraws lubricant from the container, 'and thereby reducing thepressure in the container acting upon the expansible means.

